lp3A.  3A. 
X/  G c 


1 *=•  sro rage 


OFFICE  OF  TH  E 

ILLINOIS  STATE  ENTOMOLOGIST 
URBANA,  ILLINOIS 

The  Chinch-bug  in  Illinois  in  1914 

PREPARATIONS  FOR  THE  SUMMER  CAMPAIGN 

The  present  is  the  fifth  year  of  the  continuance  of  a destructive 
outbreak  of  the  chinch-bug  in  southwestern  and  western  Illinois,  result- 
ing in  a very  heavy  loss  to  the  agriculture  of  the  state ; and  the  prospect 
at  the  present  writing  is  that  the  following  twenty-two  counties  will  be 
more  or  less  heavily  infested  this  year : — 

Bond,  Brown,  Cass,  Christian,  Clinton,  Greene,  Jersey,  Macon, 
Macoupin,  Madison,  Marion,  Menard,  Monroe,  Montgomery,  Morgan, 
Pike,  Randolph,  Sangamon,  Scott,  Shelby,  St.  Clair,  and  Washington. 

The  bugs  are  now  in  their  winter  quarters,  where  a very  small 
percentage  of  them  have  perished  during  the  winter.  From  their 
present  places  of  shelter  they  will  begin  to  scatter  over  the  country  on 
the  wing  during  this  month  of  April,  settling  where  their  food  plants 
invite  them — mainly  in  fields  of  wheat  in  neighborhoods  where  this  crop 
is  grown ; and  there  they  will  suck  the  sap  from  the  crop  plants  and 
grasslike  weeds  in  the  field,  and  will  presently  begin  to  lay  their  eggs. 

This  movement  of  dispersal  will  continue  well  into  May,  and  it 
may  carry  the  bugs  into  many  counties  additional  to  those  now  infested. 
Some  of  the  latest  to  emerge  and  fly  abroad  will  lay  their  eggs  in  oats, 
and  others  possibly  in  young  corn ; but  where  wheat  is  generally  grown, 
the  greater  part  of  this  hibernating  generation  will  first  infest  that 
crop. 

There  is  no  way  in  which  crops  exposed  can  be  protected  against 
this  spring  invasion,  or  in  which  the  old  bugs  infesting  the  small  grains, 
or  the  young  bugs  hatching  from  the  egg,  can  be  destroyed  before 
harvest  time.  The  first  opportunity  for  a successful  attack  on  the 
chinch-bug  will  come  when  the  grain  is  cut,  the  old  bugs  being  then 
practically  all  dead,  and  the  young  not  having  yet  got  their  wings.  As 
their  food  supplies  disappear  in  the  infested  fields  with  the  ripening 
and  harvesting  of  the  grain,  the  bugs  are  compelled  to  move  out  on 
foot  in  search  of  new  food  plants,  the  best  of  which  available  to  them 
at  this  time  is  corn.  It  is  the  task  of  the  farmer  to  prevent  their  escape 
from  these  harvested  fields,  and  especially  to  protect  his  corn  from 
invasion  at  harvest  time  by  the  new  generation  which  has  taken  its 
start  in  wheat. 

If  this  is  not  done,  the  wheat-field  bugs  will  first  lay  waste  the 
corn  nearest  the  wheat  to  a distance  across  the  field  varying  with  their 
number  and  the  weather  of  the  season,  and  then,  as  they  get  their  wings, 
they  will  fly  everywhere,  infesting  corn  fields  generally  and  producing 
there  a much  more  numerous  second  generation,  to  the  widespread 


2 


injury  of  the  crop.  It  is  true  that  very  wet  weather  coming  at  this 
hatching  time  may  arrest  this  process  and  so  reduce  their  number 
that  no  serious  injury  will  follow;  but  the  farmers  of  the  state  can 
hardly  afford  to  bet  their  corn  crops  that  things  will  take  so  fortunate 
a turn  this  year;  especially  as  they  can,  if  they  will,,  secure  a large 
part  or  all  of  this  result  by  their  own  activities  and  at  an  expense 
which  is  trifling  compared  with  the  values  at  stake. 

The  Illinois  Method 

What  may  be  called  the  Illinois  method  of  attack  upon  the  chinch- 
bug  consists  of  a combination  of  barriers  of  a repellent  substance  laid 
along  the  borders  of  a field  to  stop  the  movement  of  the  bugs,  with 
trap-holes  beside  it,  together  with  an  insecticide  spray  applied  to  in- 
fested corn  under  certain  special  conditions. 

This  barrier  method  was  first  used  in  McLean  county,  111.,  in 
1871,  a row  of  fence-boards  being  set  up  beside  the  infested  field  with 
coal-tar  applied  to  their  upper  edge;  but  later  in  the  same  season  the 
tar  was  simply  poured  upon  the  ground,  holes  being  dug  beside  it  to 
trap  the  bugs.  A hundred  and  fifty  barrels  of  coal-tar  were  used  for 
this  purpose  in  that  year  near  Bloomington.  This  method  was  greatly 
improved  in  1911  and  1912  by  the  substitution  of  the  petroleum  products 
known  as  road-oils  No.  6 and  No.  7;  and  in  1912  and  1913  it  was 
made  still  more  practicable  by  the  discovery  that  crude  creosote  and 
crude  carbolic  acid  might  be  used  instead  of  the  road-oils. 

The  chinch-bug  was  first  killed  on  corn  by  means  of  insecticide 
sprays  in  McLean  county  in  1882,  an  emulsion  of  kerosene  and  milk 
and  kerosene  and  soap-suds  being  successfully  used  for  this  purpose. 
This  method  was  also  improved  in  1910  by  substituting  for  the  kerosene 
a tobacco  solution  known  as  “Black  Leaf  40/’  the  efficiency  of  which 
was  increased  by  the  addition  of  soap.  In  1912  it  was  found  that  if 
a soap  solution  of  the  proper  strength  were  used,  the  tobacco  might 
be  entirely  omitted ; and  many  fields  of  young  corn  were  saved  that 
year  by  treatment  with  this  spray. 

The  usefulness  of  these  operations  depends  very  largely  upon  a 
general  participation  in  them,  since  the  individual  farmer  may  destroy 
all  the  chinch-bugs  bred  in  his  own  fields  and  yet  suffer  heavy  loss, 
later  in  the  season,  from  chinch-bugs  flying  in  from  other  farms,  where 
the  work  has  been  neglected.  An  important  part  of  this  method  is, 
consequently,  the  organization  of  communities  for  a general  cooperative 
attack  upon  the  insects  at  the  proper  time,  and  in  the  best  available 
manner.  Our  first  successful  attempts  to  this  end  were  made  in  1911, 
and  much  excellent  cooperative  work  has  been  done  in  the  later  years. 

The  Method  in  Detail 

In  a situation  like  the  present  the  first  important  undertaking 
must  be  to  arouse,  inform,  advise,  and  organize  for  cooperation  the 
farming  population  of  infested  districts.  The  field  agents  of  the 


'O’l*  41, 


3 


<o 


Entomologist’s,  office  are  keeping  close  watch  of  field  conditions 
throughout  and  around  the  area  infested  last  year;  and  by  circulars, 
posters,  newspaper  notices,  public  meetings,  and  personal  interviews, 
the  communities  concerned  will  be  kept  advised,  as  far  as  possible,  of 
what  they  have  to  expect  and  prepare  for  as  the  season  advances. 

A preliminary  circular  was  issued  February  28,  and  the  present 
one  will  be  followed  by  a third  as  soon  as  the  hibernating  chinch-bugs 
have  settled  in  the  fields  where  the  new  generation  is  to  appear. 

Mode  of  Organization. — The  organization  of  infested  districts  can 
best  proceed  by  counties ; and  the  agencies  whose  cooperation  is  essen- 
tial in  the  beginning  are  the  business  men’s  organization  at  the  county- 
seat,  the  county  officers  of  the  farmers’  institute,  and  the  local  papers  of 
the  county.  As  soon  as  the  fact  is  evident  that  widespread  injury  to 
wheat  and  corn  is  impending  in  any  county,  a conference  should  be 
promptly  called  of  the  editors,  farmers’  institute  officers,  and  officers 
of  the  commercial  club  or  other  business  organization,  and  measures 
should  be  taken  for  mass-meetings  to  be  held  at  the  larger  towns,  and 
addressed  by  a representative  of  the  Entomologist’s  office  who  will 
discuss  the  local  situation  and  the  measures  necessary  to  be  taken.  At 
this  meeting  township  lieutenants  should  be  appointed,  to  call  and 
provide  for  school-house  meetings,  especially  in  districts  where  the 
danger  is  greatest.  At  these  district  meetings  practical  talks  should  be 
made,  circulars  distributed,  questions  answered,  and  everything  made 
ready  for  the  actual  harvest-time  operation  against  the  chinch-bug. 

At  the  county-seat  meeting  conclusions  should  be  reached  as  to 
the  means  of  supply  of  the  necessary  materials  to  farmers  at  the  lowest 
possible  cost.  Wholesale  rates,  plus  transportation,  can  usually  be 
arranged  for  through  an  agent  or  committee  of  the  business  men’s 
association.  An  estimate  of  the  amount  of  the  materials  required 
should  be  sent  by  each  man  to  the  county  agent  as  early  as  possible,  in 
order  that  sufficient  supplies  may  be  certainly  on  hand  when  they  are 
first  needed.* 

The  success  of  the  whole  movement  will  depend  very  largely  upon 
the  spirit  with  which  it  is  taken  hold  of  by  the  county  leaders  in  town 
and  country  business,  and  especially  upon  the  active  influence  of  one 
farmer  upon  another  throughout  each  neighborhood. 

The  Field  Operation. — As  wheat-harvest  draws  near  each  owner 
of  an  infested  field  should  make  his  preparations  to  prevent  the  escape 
of  the  bugs  from  it,  especially  on  the  side  where  fields  of  corn  or  oats 
adjoin  it. 

*At  Greenville  during  the  summer  of  1912  the  county  commercial  club  handled  the  road- 
oil  at  cost,  and  aided  generally  in  the  campaign.  At  Litchfield  in  1913  the  retail  merchants’ 
association  handled  the  road-oil  at  cost,  and  its  officers  aided  the  work  in  every  possible  way. 
At  Carlinville  the  oil  was  handled  at  cost  by  a member  of  the  commercial  club,  and  the  mer- 
chants of  that  city  raised  over  $200  as  a bounty  fund  for  the  payment  of  $2  a bushel  for 
chinch-bugs  delivered  to  their  agent  before  the  10th  day  of  July.  Twenty-seven  bushels  of 
chinch-bugs  were  actually  brought  in,  and  several  times  as  many  might  have  been  delivered 
if  those  destroying  them  had  taken  the  trouble.  Seven  and  a quarter  bushels  were  caught,  in 
fact,  around  one  field  in  a week,  and  as  the  road-oil  lines  and  post-hole  traps  had  been  in 
effective  operation  for  the  two  weeks  preceding,  twenty  bushels  is  a fair  estimate  of  the 
quantity  of  chinch-bugs  caught  about  this  one  field.  When  we  take  account  of  the  fact 
that  a single  bushel  at  harvest  time  contains  over  eight  million  bugs,  and  that  each  female 
of  this  generation  would  commonly  lay  from  100  to  300  eggs,  we  may  form  some  idea  of 
the  effect  of  such  destruction  upon  the  numbers  of  the  second  generation. 


4 


The  materials  to  be  poured  upon  the  ground  for  making  the  barrier 
lines  are  No.  7 road-oil  as  made  by  the  Standard  Oil  Company 
at  its  refinery  in  Whiting,  Ind.,  or  crude  creosote  (containing  8 
to  10  per  cent,  of  tar  acids),  or  crude  carbolic  acid,  to  be  ob- 
tained from  almost  any  large  wholesale  dealer  in  paints  or  drugs. 
The  No.  7 road-oil  of  the  Whiting  refinery  is  a nearly  perfect  material 
for  this  purpose,  and  it  has  been  longer  and  more  thoroughly  tried  out 
than  the  other  substances.  It  has,  however,  the  disadvantage  that  it  is 
not  on  the  general  market,  and  must  be  made  in  advance  for  this 
particular  use.  Advance  arrangements  must  consequently  be  made  for 
the  amount  likely  to  be  needed  for  the  season ; and  it  is  difficult  to  dis- 
pose of  any  surplus  remaining.  The  creosote  and  carbolic  acid,  on 
the  other  hand,  are  common  market  products,  much  used  for  other 
purposes,  and  can  be  had  in  any  quantity  by  giving  previous  notice  to 
insure  a sufficient  supply  within  reach  at  the  time. 

The  cost  of  the  road-oil  necessary  to  maintain  a mile  of  the  barrier 
for  an  average  season  will  be  $9  this  year,  and  that  of  the  creosote 
will  be  $13.  If  we  take  into  account  the  labor  of  the  farmer  and  his# 
team  in  the  preparation  of  the  ground  for  the  road-oil  or  the  creosote, 
respectively,  we  must  add  $23  per  mile  for  the  road-oil  and  $15  for 
the  creosote  or  carbolic  acid.  The  total  cost,  on  this  basis,  will  be  $32 
a mile  for  the  road-oil  treatment,  and  $28  a mile  for  that  with  creosote. 

The  most  difficult  part  of  the  field  operation  is  the  preparation  of 
a path  along  the  border  of  the  infested  field  upon  which  to  pour  the 
materials  for  the  barrier  line.  For  the  creosote  it  is  only  necessary 
that  a bare  and  fairly  level  surface,  reasonably  firm,  should  be  made 
ready ; but  for  the  road-oil  a hard  smooth  surface  is  much  more  essen- 
tial. The  latter  must  be  kept  so  sticky  that  the  bugs  can  not  cross  it, 
and  consequently  must  not  be  permitted  to  sink  into  the  ground.  The 
creosote  acts  by  its  offensive  odor,  such  that  the  bugs  will  not  cross  it 
even  though  they  might  do  so  if  they  would,  and  these  odors  are  given 
off  from  the  saturated  soil  after  the  fluid  has  soaked  into  the  ground. 

No  single  method  of  preparing  the  line  will  answer  in  all  places 
and  under  all  conditions,  and  much  must  be  left  to  the  experience  and 
judgment  of  the  farmer  himself.  The  following  discussion  of  this 
part  of  the  subject  is  taken  from  a manuscript  report  of  Mr.  W.  P. 
Flint,  my  field  assistant  for  central  Illinois,  who  will  be  in  general 
charge  of  the  state  campaign  against  the  chinch-bug  this  year. 

“The  chinch-bug  barriers,”  he  says,  “are  prepared  by  making  a 
smooth  path  around  the  wheat  field  just  before  harvest,  and  pouring 
upon  this  a narrow  line  of  some  substance  which  the  bugs  can  not  or 
will  not  cross.  On  the  side  of  this  line  next  the  wheat,  post-holes  are 
dug  about  20  feet  apart  and  from  eighteen  inches  to  two  feet  in  depth. 

“Under  ordinary  weather  conditions,  such  a barrier  may  be  very 
easily  made;  but  with  weather  as  dry  as  that  of  1913,  it  was  difficult 
to  make  a smooth  path  around  the  field.  If  this  can  be  made  beside  a 
lane  or  public  road,  where  the  ground  is  compact  and  firm,  and  where 
there  is  very  little  vegetation  to  be  removed,  it  is  a comparatively 
simple  matter;  but  where  the  path  is  made  in  the  edge  of  a wheat 


5 


Road-oil  line  around  a field  of  wheat  nearly  destroyed  by  chinch-bugs.  Note  the 
perfect  condition  of  the  corn  field  beside  the  wheat. 


6 


field  or  in  the  cultivated  soil  of  a field  of  corn,  it  is  more  difficult  to 
make  a path  smooth  and  firm  enough  to  hold  the  road-oil  for  any 
length  of  time  at  high  midsummer  temperatures.  If  road-oil  is  to  be 
used,  the  path  should  have  a slight  depression  in  the  center,  to  keep 
the  oil  from  spreading. 

“Some  of  the  best  paths  in  stubble  ground  have  been  made  during 
the  past  two  years  with  a drag  of  heavy  plank  about  six  feet  long, 
cut  to  a V-shape  at  the  front  end,  with  strips  of  iron,  sharpened  to  a 
cutting  edge  below,  attached  on  both  sides  of  the  “V”,  and  with  a 
small  share  in  the  center.  A strip  of  iron  an  inch  square,  attached 
to  the  center  of  the  under  side  of  the  plank,  makes  a slight  groove  in 
the  path. 

“On  cultivated  ground,  the  best  paths  have  been  made  by  drawing 
a heavy  drag  back  and  forth  until  the  ground  is  smooth  and  firm,  a 
groove  being  afterwards  made  by  running  an  empty  wagon  over  the 
ground  so  that  one  wheel  comes  in  the  center  of  the  path.  Good  paths 
have  also  been  made  by  dragging  the  drive-wheel  of  a binder  or  mower 
over  the  ground ; or,  if  a road-grader  is  available,  this  may  be  used  to 
advantage. 

“Some  have  plowed  a shallow  furrow,  cleaning  it  out  with  a spade 
or  hoe;  and  others  have  thrown  up  two  back-furrows,  smoothing  the 
ridge  by  rolling,  and  making  a line  along  its  center.  For  a road-oil 
line,  such  a ridge  should  be  made  at  least  a fortnight  in  advance,  to 
allow  the  ground  to  settle.  This  is  a good  practice  with  any  kind  of  a 
path,  as  the  chinch-bugs  sometimes  leave  the  field  before  the  wheat  is 
■cut,  and  delay  until  they  begin  to  move  may  cause  the  loss  of  corn  for 
a number  of  rows  next  the  infested  wheat. 

“If  creosote  is  to  be  used,  the  surface  on  which  it  is  to  be  poured 
need  not  be  so  carefully  prepared,  a fairly  smooth  path  from  six  to 
eight  inches  wide  being  all  that  is  necessary.  In  fact,  several  used  this 
■substance  successfully  last  year,  where  no  path  at  all  had  been  made, 
iby  pouring  it  on  the  bare  ground  of  the  cultivated  corn-field  or  on  the 
grass  of  a pasture ; and  this  may  be  done  in  an  emergency  where  the 
hugs  leave  the  wheat  unexpectedly  before  harvest.  The  amount  of 
creosote  necessary  and  the  labor  required  for  the  maintenance  of  a 
line,  may  be  considerably  reduced  by  using  as  a carrier  coarse  salt,  or 
stable  manure  as  free  as  possible  from  straw.  For  this  purpose  the 
manure  should  be  spread  along  the  center  of  the  prepared  path  in  a way 
to  make  a ridge  about  four  inches  wide  and  two  inches  high.  The 
creosote  or  carbolic  acid  poured  upon  this  ridge  is  absorbed  by  it,  and 
held  for  a much  longer  time  than  if  spread  upon  the  bare  ground.  If 
salt  is  used,  a similar  but  narrower  line  may  be  laid  by  hand,  a barrel 
of  salt  being  sufficient  for  about  a mile  of  the  line.  This  last  material 
has  no  advantage  over  the  manure,  where  both  may  be  had,  and  it 
has  the  defect  that  it  may  be  dissolved  by  a heavy  rain. 

“The  post-hole  traps  should  be  so  placed  that  the  tar  line,  when 
laid,  will  touch  each  one,  and  the  mouth  of  the  hole  should  flare  a little, 
giving  a slightly  sloping  surface.  This  should  be  kept  well  dusted,  so 
Jthat  the  bugs  can  not  maintain  a foothold  and  will  fall  back  into  the 


7 


An  unprotected  corn  field,  1912.  The  chinch-bugs  entered  it  from  the  field  of  wheat, 
a little  of  which  is  shown  in  the  foreground. 


8 


hole  if  they  attempt  to  climb  out.  This  is  especially  likely  to  happen  if  a 
shower  of  rain  occurs.  As  a preparation  for  this,  several  farmers  last 
year  laid  in  a supply  of  sacks  of  fine  dust  when  the  weather  was  dry, 
using  this  to  keep  the  trap-holes  in  the  best  condition. 

“For  killing  the  bugs  as  they  collect  in  the  holes  the  simplest 
method  is  to  pour  a little  kerosene  into  each  from  time  to  time;  and 
if  the  bugs  accumulate  in  large  numbers,  water  may  be  poured  in  first, 
and  the  kerosent  on  that. 

“It  remains  to  describe  the  method  of  laying  the  line  on  the 
prepared  path.  If  road-oil  is  used,  a stream  half  an  inch  thick  or  less 
may  be  poured  from  a pot  with  a tubular  spout;  or,  more  conve- 
niently perhaps,  a hole  may  be  made  in  the  bottom  of  a large  tin  pail 
and  near  one  side,  into  which  a whittled  stick  or  similar  plug  may  be 
fitted,  long  enough  to  reach  above  the  top  of  the  pail.  When  this 
is  filled  with  road-oil,  the  plug  is  withdrawn  and  the  oil  streams  out  of 
the  hole  as  one  walks  slowly  along,  carrying  the  pail  steadily  to  make 
an  even  line.  A stream  which  will  spread  on  the  ground  to  the  width 
of  one’s  finger  is  quite  sufficient  for  the  first  treatment,  and  the  hole 
in  the  bottom  of  the  pail  should  be  made  large  enough  to  make  a line 
of  this  width  when  the  road-oil  is  somewhat  thick  with  the  cold.  The 
size  of  the  stream  when  the  oil  is  more  fluid,  as  the  day  warms  up, 
may,  of  course,  be  readily  regulated  by  means  of  the  plug. 

“Creosote  or  carbolic  acid  may  be  best  applied  in  a similar  way. 
A hole  the  size  of  a 6-penny  or  4-penny  nail  should  be  made  in  the  side 
of  a tin  pail  near  the  bottom,  and  from  this  the  fluid  will  spout  out 
freely  enough  to  enable  one  to  lay  the  line  about  as  fast  as  he  would 
naturally  walk.” 

Whatever  materials  are  used,  the  line  must  be  freshened  from  time 
to  time  by  pouring  more  oil  or  creosote  upon  it.  The  road-oil  line  must 
be  renewed  as  soon  as  the  surface  becomes  dry — once  in  two  or  three 
days,  more  or  less,  here  or  there,  according  to  the  soil  and  the  tempera- 
ture. The  hotter  the  weather  the  more  fluid  the  oil  becomes  and  the 
sooner  it  soaks  into  the  ground.  Under  fairly  favorable  conditions, 
No.  7 oil  may  continue  to  turn  the  bugs,  after  the  line  is  well  established, 
for  a week  or  ten  days  without  renewal.  The  creosote  and  carbolic 
acid,  on  the  other  hand,  are  effective  only  so  long  as  the  odor  is  suffi- 
ciently strong  to  repel  the  bugs,  and  it  is  commonly  necessary  to  renew 
these  substances  every  day.  The  person  in  charge  should  at  least  walk 
along  the  lines  once  a day  when  the  bugs  are  in  active  movement,  and 
strengthen  the  barrier  as  he  finds  it  necessary. 

Various  modifications  of  the  above  modes  of  operation,  and  many 
experiments  with  other  more  or  less  available  materials,  have  been  made 
by  us  in  the  course  of  the  last  few  years,  the  particulars  of  which  will 
not  be  given  here,  as  they  may  be  obtained  from  the  field  agents,  by 
those  interested,  when  the  time  comes  for  active  work. 

The  Dusty  Furrow. — “The  oldest  barrier  is  probably  the  dusty 
furrow  or  dusty  strip,  made  between  the  wheat  and  the  corn  by  plow- 
ing a shallow  dead-furrow,  or,  better,  two  or  three  such  furrows,  side 
by  side,  and  dragging  a log  back  and  forth  repeatedly  in  them.  Some 


9 


Fig.  3.  A protected  corn  field,  1912.  Road-oil  and  post-hole  traps  between  the  corn  and  the 
wheat,  by  which  millions  of  the  bugs  were  caught. 


10 


of  the  best  barriers  have  been  made  during  the  past  two  years  by 
plowing  two  or  three  furrows  about  a foot  and  a half  apart,  then 
fastening  together  two  or  three  logs,  eight  or  ten  inches  in  diameter 
and  four  to  six  feet  long,  side  by  side,  with  strips  of  board  nailed  across 
the  tops,  making  the  distance  between  the  logs  the  same  as  that  be- 
tween the  furrows.  By  means  of  this  drag  one  can  keep  up  two  or 
three  furrows  with  the  same  labor  that  would  be  needed  for  one.  To 
raise  the  cross-boards  so  that  they  will  not  drag  on  the  ridges  between 
the  furrows,  it  will  generally  be  found  necessary  to  nail  strips  of  board 
or  plank  on  the  top  of  the  logs,  to  which  the  cross-strips  may  be 
fastened.  On  some  soils,  during  dry  weather,  very  effective  work  has 
been  done  by  this  method,  but  on  other  soils  it  is  useless,  as  a layer  of 
sufficiently  fine  dust  can  not  be  made.  Furthermore,  the  slightest 
shower  at  any  time  will  make  the  surface  firm  enough  to  permit  the 
bugs  to  cross ; and  this  method  can  never  be  depended  on  for  controll- 
ing a chinch-bug  movement.  This  kind  of  a barrier  is  much  less  ex- 
pensive than  the  others,  but  in  our  climate  it  is  mainly  useful  in 
emergencies  and  when  weather  conditions  are  temporarily  favorable.” 

Many  chinch-bugs  caught  in  the  dusty  furrow,  particularly  the 
young,  are  killed  by  exposure  to  the  heat  and  dust,  and  by  the  dragging 
process  necessary  to  keep  the  furrows  in  good  condition.  Many  of 
the  older  bugs  are  likely  to  be  crowded  out  of  the  furrow,  however,  by 
this  means,  and  so  allowed  to  escape.  Indeed,  they  will  gradually  pull 
down  the  dust  on  the  side  of  the  furrow  by  their  incessant  efforts  to 
climb  up,  and  will  thus  make  a way  out.  It  is  desirable,  consequently, 
that  they  should  be  killed  in  the  bottom  of  the  furrow  at  least  once  a 
day.  This  can  best  be  done  by  the  use  of  a gasoline  blast  torch  of  a kind 
now  made  by  the  Turner  Brass  Works,  at  Sycamore,  111.,  and  called  by 
them  the  “locust  torch.”  A much  better  but  more  costly  machine 
for  this  purpose  is  the  so-called  “cactus  burner”  of  the  southwest. 
Our  own  experiments  with  gasoline  torches  against  the  chinch-bug 
were  made  in  1902,  and  they  have  not  been  lately  repeated  on  a 
large  enough  scale  to  permit  me  to  recommend  this  apparatus  on 
my  own  experience.  Professor  Headlee  has  lately  gone  much 
farther  with  the  locust  torch  in  Kansas,  and  says  that  it  has  “proven 
itself  admirably  adapted  to  our  needs,  for  not  only  are  we  able 
to  destroy  the  bugs  by  simply  passing  the  flame  along  the  furrow 
where  they  have  collected,  but  without  inconvenience  the  furrow 
can  be  repaired  as  often  as  is  necessary  by  dragging  a log  or  trough 
through  it.”  This  torch,  he  says,  “is  the  most  efficient  because  it 
furnishes  a strong  blue  flame  six  or  eight  inches  long  and  two  and 
a half  to  three  inches  through,  which  fills  the  dusty  furrow  where 
the  bugs  are  struggling  with  a strong  blast  of  blue  flame  and  is  not 
blown  out  by  the  wind.  The  purchaser  should  insist  on  getting  a torch 
having  these  specifications.” 

Insecticide  Sprays. — There  are  two  conditions  under  which  it  has 
proved  highly  profitable  to  spray  corn  infested  by  chinch-bugs.  One 
of  these  cases  is  where  young  corn  is  attacked  in  spring  by  the  old 
bugs  as  they  come  out  from  their  winter  quarters  and  by  the  young  as 


II 


these  hatch  from  the  egg.  The  other  is  where,  through  neglect  or 
accident,  bugs  are  permitted  to  escape  from  a wheat  field  to  a corn 
field  adjacent,  and  accumulate  there  in  great  numbers  on  the  outer  rows 
previous  to  scattering  over  the  field.  A very  effective  insecticide  is 
made  by  putting  a strong  tobacco  extract  known  as  “Black  Leaf  40” 
and  any  good  laundry  soap  into  water  at  the  rate  of  *4  ounce  of  the 
tobacco  extract  and  1 ounce  of  the  soap  to  a gallon  of  water.  A mere 
solution  of  3 ounces  of  certain  kinds  of  laundry  soap  to  the  gallon  of 
water  is,  in  fact,  nearly  as  effective  with  the  tobacco  omitted.  These 
fluids  must  be  applied  to  the  corn  thoroughly  enough  to  wet  every 
bug,  but  carefully  enough  to  prevent  filling  the  “curl”  or  cone-shaped 
cavity  among  the  leaves  at  the  top  of  the  plant. 

It  has  been  found  that  certain  kinds  of  soap  are  much  more  ef- 
fective than  others,  the  best,  in  our  experience,  being  the  common 
brands  known  as  “Rub-no-more,”  “Mottled  German,”  “American  Fam- 
ily,” and  “Peosta,”  to  be  preferred  about  in  the  order  named.  For  the 
best  results,  soft  water  should  be  used,  but  this  is  not  essential. 

The  best  sprayer  for  chinch-bug  work,  within  our  knowledge,  is 
a small  compressed-air  sprayer  carried  by  a strap  over  the  shoulder, 
and  holding  about  three  gallons  and  a half  of  liquid.  It  is  charged  with 
air  by  a few  strokes  of  the  plunger,  and  the  spray  is  forced  out  by  the 
pressure.  Such  sprayers,  costing  from  $4  to  $6,  according  to  the 
material  of  which  they  are  made,  can  be  bought  from  any  large  hard- 
ware or  mail-order  house.  The  nozzle  which  has  given  the  best  result 
is  an  adjustable  one  of  the  “Kant-Klog”  type,  so  adjusted  as  to  give  a 
straight  stream  instead  of  a broken  spray. 

Additional  copies  of  this  circular  may  be  had  in  any  number  by 
application  to  the  undersigned.  Those  receiving  it  are  earnestly  re- 
quested to  aid  in  its  distribution  in  their  respective  neighborhoods,  and 
also  to  communicate  their  observations  and  the  results  of  their  ex- 
perience either  to  this  office  or  to  W.  P.  Flint,  1231  W.  Edwards  St., 
Springfield,  111. 

Stephen  A.  Forbes, 

State  Entomologist. 

Urbana,  111., 

April  16,  1914. 


